This NHS content is written for people in England. Medicine names, availability, prescribing and services may differ in other countries.
Pseudoephedrine is a decongestant that helps you breathe more easily if your nose is stuffy or blocked (nasal congestion). This happens when blood vessels in the cavities in your nose (sinuses) become swollen.
Pseudoephedrine works by reducing this swelling and that helps mucus and air flow more freely.
You can get a blocked or stuffy nose when you have:
You can buy pseudoephedrine from pharmacies. It comes as tablets and a liquid that you swallow. You can buy these from a pharmacy in a pack of 12 tablets or 100ml of liquid.
If you need more than this, you'll need a prescription from a doctor.
Pseudoephedrine also comes mixed with other medicines to treat the symptoms of coughs, colds and allergies. These include Benadryl Allergy Relief Plus and Benylin Day & Night.
Pseudoephedrine mixed with other medicines comes as tablets, capsules and a liquid that you swallow.
View the original NHS website page ↗. Refreshed 19 August 2026.
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